中国人 框 variant was originally developed from European box variant, and its volume is often large. With the opening up of China’s economy and the vigorous development of market economy, about 90’s, the American box transformer entered the Chinese market, and with its unique characteristics in China market obtained rapid development. High-grade box substation export has also become an important goal of the development of China’s substation, through the high-grade box substation to open up foreign markets, it can be said that the Chinese high-end box substation exports by the United States box substation influence